The focus of the several projects within this Program-Project is to increase knowledge of physical, chemical and biological properties of lipids fundamental to the understanding of the function of lipids in normal and disease processes. Investigations range from frankly fundamental ones to those directly relevant to disease states. They include studies of analytical methods and their application to biological problems, studies of the properties of isolated lipids and the relationship of these properties to the function of lipids in living systems, studies of the effect of structure upon biological activity, studies of interactions of lipids of microorganisms and host tissue, and studies which apply existing knowledge to the control of disease.